Abbess Nazaria of Varatec: Spiritual Moderation

The path which we walk along in the spiritual life is narrow: we must keep to the middle of this path and avoid falling from either side. The fall from the left side comes when we are negligent in our life of prayer and fasting; the fall from the right side comes when we are overly zealous and impose rigors on ourselves which we are not able to maintain and which also lead to the deadly sin of pride. The temptations and perils of the fall from the right side are the most dangerous.
+Abbess Nazaria of Varatec, from Come, Follow Me: Orthodox Monasticism in Moldavia, by Mother Cassiana, Chapter 6. First Week of Great Lent

Evagrius Ponticus: Reading, vigils, and prayer

Reading, vigils and prayer - these are the things that lend stability to the wandering mind. Hunger, toil and solitude are the means of extinguishing the flames of desire. Turbid anger is calmed by the singing of Psalms, by patience and almsgiving. But all these practices are to be engaged in according to due measure and at the appropriate times. What is untimely done, or done without measure, endures but a short time. And what is short lived is more harmful than profitable.
Evagrius Ponticus, from The Praktikos, #15